package com.atguigu.observer.improve;

/**
 * @program: design-patterns
 * @author: yangshen
 * @description: 核心类的接口，让WeatherData来实现，
 * @create: 2022-03-08 14:35
 **/
public interface Subject {

    public void registerObserver(Observer observer);
    public void removeObserver(Observer observer);
    public void notifyObserver();
}
